Figural conditions affecting the formation of anomalous surfaces: overall configuration versus single stimulus part

Two kinds of figural condition affecting the formation of anomalous surfaces were examined in three experiments. The strengths of two factors (figural incompleteness and width of the inducing areas) were compared in order to determine: i) which of the two factors is more effective in the creation of the illusion, and ii) whether the inducing-area width is so important that it can also destroy the illusion when the inducers are clearly incomplete or 'gappy'. The results show that the inducing-area width seems to predominate over figural incompleteness in the formation of anomalous surfaces.